Keith Monks Audio no longer in business?

No problem. Given the overall design, and depending on the robustness of the parts, it could last you a lifetime. I've seen some pretty old machines still in operation. For a vacuum RCM, I doubt you'll find much better, but it depends on what parts were originally installed in that set up you have. Hope you get it sorted. And let us know what the status of the company is- I sort of gave up trying to deal with England directly, but am well pleased with my machine. 
bill 

Again thank you.
I do find it frustrating that that the company is not accessible... 
Any replacement RCM will most likely be a different brand.

Here is the list of suppliers/dealers from the Keith Monks page for North America. Scroll down and you’ll see it. I think Seth has a full-time job (at least he did) in the city. This should also have other dealers in the States. https://www.vinyldiscovery.com/north-america
PS: I have also dealt with Don Better in Ohio and Ne Ultra Plus in Texas. They are still listed as dealers on that page as well. One of them should know what's up and be able to help you. 

whart, thank you for your response.
Do you have a contact email for Seth Winner Studios, as I did a search but couldn't find one.
Again, thank you.

I have a Monks Omni, and at least in the States, they seem to prefer that you work through a retail dealer. I had some interaction with Jonathan, but communications were sometimes spotty, since he has a ’regular’ job I think. Seth Winner Studios, in Long Island, does the repair and maintenance work for the libraries and institutions here in the States and there’s another outfit in Canada for institutional customers. I know Seth--he was responsible for the Library of Congress machines. He’s pretty good guy, you might shoot him an email and ask him what’s up. (Seth was around in the days when Keith was alive, so he knows his stuff).
PS: Not sure about that Wisconsin office- my impression was it wasn't a big operation on this side of the pond.